There exist in the prior art an arrangement of the kind referred to above which permits the drive of the load carrying device to be influenced in the lateral sense through a lateral movement of a lifting cable. When lifting something using such prior art load hoist arrangements there is often a problem with self-induced vibrations or excessive swinging in the load hoist arrangement. The changes in acceleration and direction, induced manually by an operator, to the load carrying device often makes the load carrying device start swinging. Once it has started swinging, especially if the load is heavy, it is difficult to stop the motion and sometimes the supporting structure will follow swinging, leading to e.g. a decrease in maneuverability, a risk for accidents, etc.
In SE 466 960 a load hoist arrangement is presented having a traverse device comprising support elements for supporting a traveling bridge arranged to travel along said support elements and a carriage arranged to travel back and forth on said traveling bridge. Two motors are arranged on the support structure and provided with cables connected to the traveling bridge, which bridge is located between the motors, for the purpose of driving said traveling bridge in each of its mutually opposite directions along the support structure. There is also a need for a load hoist arrangement which supports motions in a lateral plane and not only along a line.
By positioning the motors on the support structure, a relatively stable working environment for the heavy motors is accomplished. However, these motors need to communicate with the transmitters arranged on preferably the moving parts of the load hoist arrangement in order to perform a controlled movement. Thus, there are a lot of cables interconnecting static components with movable parts on such prior art load hoist arrangements. These cables are often provided with sensitive connections and couplings, which in this dynamic environment will be quite exposed to wear, providing a risk for e.g. less accurate motion control and an increasing need for maintenance. In addition there is also a need for a load hoist arrangement which is easy and fast to install.